content
Defines what the sound is and expresses the general category of the content such as movie, speech, or beep/ringtone. The audio framework uses content type information to selectively configure audio post-processing blocks. While supplying the content type is optional, you should include type information whenever the content type is known Defaults to AudioAttributes.CONTENT_TYPE_MUSIC
See also
<a href="https://source.android.com/devices/audio/attributes#content-type">Content type</a>